Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: jazbo8 on April 30, 2014, 07:21:32 am

Title: My 3Watter - Princeton Meets AX84 4-4-0
Post by: jazbo8 on April 30, 2014, 07:21:32 am: Prompt by SilverGUN about the lack of updates on my blog, I finally got off my a$$ and finished a simple build, it's a mash up of Princeton and AX84 4-4-0 Studio, you can read about it here (http://jazzbo8.wordpress.com/2014/04/30/whats-old-is-new-again-introducing-the-3watter/).

Comments and suggestions are welcomed.
Title: Re: My 3Watter - Princeton Meets AX84 4-4-0
Post by: SILVERGUN on April 30, 2014, 07:47:06 am: Quote from: jazbo8 on April 30, 2014, 07:21:32 am
Prompt by Silverfox about the lack of updates on my blog, I finally got off my a$$ and finished a simple build, it's a mash up of Princeton and AX84 4-4-0 Studio, you can read about it here (http://jazzbo8.wordpress.com/2014/04/30/whats-old-is-new-again-introducing-the-3watter/).
It's Silver-GUN, and you're not the only one who gets us mixed up....... :icon_biggrin:

Nice update and that's a cool little build you got there!.....(of course I snatched up the schematic)

The demo does a great job of showing the range of clean to mean.

My suggestion(if you get the chance) would be to try this idea of using the 3 Watter as a "pre-amp" into one of you're other amps and see how it sounds, and if there's anything you like/dislike......pic taken from this thread: http://el34world.com/Forum/index.php?topic=16934.0 (http://el34world.com/Forum/index.php?topic=16934.0)

Thanks for the update!
Title: Re: My 3Watter - Princeton Meets AX84 4-4-0
Post by: jazbo8 on April 30, 2014, 08:05:34 am: Sorry about the mix-up... I was reading the Herzog thread, indeed it's an interesting idea, will report back soonish... :icon_biggrin:
Also, this little amp takes pedals pretty well, I tried the FatBastard (FET booster) and the RAT - not bad at all, threw in a little delay with Ibanez DE-7 which made the amp sound bigger, but I do like the fact that the amp sounds decent without much help.
Title: Re: My 3Watter - Princeton Meets AX84 4-4-0
Post by: SILVERGUN on April 30, 2014, 08:46:43 am: What voltages are you seeing at D1 and D2?....just curious

I'll be using LED cathode bias in one stage and I'm wondering if we should start listing the voltage specs of the LEDs on the schematic for future reference...
I guess it wouldn't hurt.
Title: Re: My 3Watter - Princeton Meets AX84 4-4-0
Post by: jazbo8 on April 30, 2014, 09:12:33 am: Quote from: SILVERGUN on April 30, 2014, 08:46:43 am
What voltages are you seeing at D1 and D2?....just curious

I'll be using LED cathode bias in one stage and I'm wondering if we should start listing the voltage specs of the LEDs on the schematic for future reference...
I guess it wouldn't hurt.

Didn't really measure them, but IIRC from my previous builds, the red LED is 1.2V and the white LED is 3V+, since the terminal strip board was so small, I had to save on part count, each LED replacing a resistor and a capacitor, plus they glow :icon_biggrin:
Title: Re: My 3Watter - Princeton Meets AX84 4-4-0
Post by: kagliostro on April 30, 2014, 11:15:31 am: Hi Jazbo8

So actually the amp has no TS and 2 output tubes ....... but .... which is actually the primary impedance of the OT ?

10k a-a as in the schematic or adding the second tube you swapped to a 5k a-a OT ?

Thanks

Franco

p.s.: Here SilverFoxGun http://www.airsoft-squared.com/it/review/147/silver-fox-cap-gun (http://www.airsoft-squared.com/it/review/147/silver-fox-cap-gun) :icon_biggrin:
Title: Re: My 3Watter - Princeton Meets AX84 4-4-0
Post by: jazbo8 on April 30, 2014, 12:25:12 pm: Quote from: kagliostro on April 30, 2014, 11:15:31 am
Hi Jazbo8

So actually the amp has no TS and 2 output tubes ....... but .... which is actually the primary impedance of the OT ?

10k a-a as in the schematic or adding the second tube you swapped to a 5k a-a OT ?

Thanks

Franco

p.s.: Here SilverFoxGun http://www.airsoft-squared.com/it/review/147/silver-fox-cap-gun (http://www.airsoft-squared.com/it/review/147/silver-fox-cap-gun) :icon_biggrin:

The amp does have a TS, but I installed a bypass switch, and prefer to run it without the TS (like in the soundclip) since the volume and tone controls on the guitar can already provide a variety of tone (for me). The OPT is 10k:8 for a pair of 6SN7 in parallel.
Title: Re: My 3Watter - Princeton Meets AX84 4-4-0
Post by: SILVERGUN on April 30, 2014, 03:06:00 pm: Quote from: jazbo8 on April 30, 2014, 12:25:12 pm
The amp does have a TS, but I installed a bypass switch, and prefer to run it without the TS (like in the soundclip) since the volume and tone controls on the guitar can already provide a variety of tone (for me). The OPT is 10k:8 for a pair of 6SN7 in parallel.
When running without the TS, what value coupling cap are you using (on the recording)?
Title: Re: My 3Watter - Princeton Meets AX84 4-4-0
Post by: kagliostro on April 30, 2014, 03:28:19 pm: Thanks for the info .......... I forgot, what about B+ ?

Thaks

Franco
Title: Re: My 3Watter - Princeton Meets AX84 4-4-0
Post by: jazbo8 on May 01, 2014, 12:34:28 am: The TS is bypassed with 0.047uF, and the B+ is around 280V, but anything from 250-320V should work just fine.
Title: Re: My 3Watter - Princeton Meets AX84 4-4-0
Post by: kagliostro on May 01, 2014, 06:14:29 am: Thanks Jazbo

K